When is the Cold too Cold?

I keep moving at a constant pace to try to find that perfect place where I am warm but not overheating. My nose is running faster than I am, and I find myself continually blowing snot and then wiping the leftovers on the backside of my mittens. I pull my buff back up over my mouth and nose to protect myself from the sharp wind. I once again check to make sure that my jacket is zipped to the very top and tighten my hood even more for ultimate protection.

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I am now just 7 miles into a hilly long run and my nipples are frozen. No, not those nipples, but the ones on my Salomon soft flasks, so hydration is already out the window. I try to remedy my thirst from time to time by opening my mouth and allowing the blustery falling snow to swoop in. Despite only having two frozen flasks, I pull shot blocks out of my pack in hopes of downing some calories. They are rock solid; attempting to eat them in this state would likely result in a trip to the dentist or a need for the Heimlich maneuver. I decide to tuck them into my mitten in hopes of softening them up and realize that my mittens are now frozen stiff from all the snot I have mopped up with them.

I try to shrug it all off and continue to put miles behind me. This works for a while, but as my body starts to crave calories and my pace slows, I start to get cold. Cold fingers turns into cold hands. My arms locking up, then as my backside gets cold my hamstrings become tight rubber bands that govern the length of my stride. Everything is shutting down and I want to slow to a walk, but my mind knows that I have to keep moving or I will be in serious trouble.

When I left the house, the temperature was -20 degrees, so I layered up clothing, filled my flasks with hot water and made sure I had little to no skin exposed. I had eaten a little extra knowing that it takes calories to generate body heat and made a thermos with tea to consume immediately after my run. The previous weekend I had run 24 miles on the treadmill due to inclement weather, so I really felt the need to be outside running different surfaces and varied pitches. The question that keeps coming to mind, though, is “How cold is too cold?”

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After doing some research there seems to be no definite answer on what temperature should deter you from running outside. What is clear is that there are three main factors that should be taken into consideration when determining what to wear and if running outside is a good idea: air temperature, wind speed and moisture. Taking into account these three factors, along with your prescribed workout, you can determine that best way to dress appropriately and decide if running outside is worthwhile.

But how does the cold affect your exercise? A study done by Myra Nimmo in the United Kingdom examined how the body adapts to exercising in the cold and found that your body burns more carbohydrates, less fat and has a higher oxygen consumption at any intensity. She also found that explosive power is limited by the temperature of the muscles and in general, athletes are vulnerable to performance deficits.

What kind of numbers are we talking? Studies report that at a temperature of 0 degrees Fahrenheit, there is an 8 to 9 percent decline in performance. Certainly something under 10 percent doesn’t sound drastic, but to put this into perspective, if at 50 degrees you are running an 8-minute mile, then at 0 degrees your pace would be 8:41. In other words, if you are running for distance, your times may be considerably slower, while your effort can be considerably higher.

Hydration is also affected. Cold temperatures increase our respiratory fluid loss, our sweat evaporates more quickly in cold air and our bodies’ thirst response is diminished. Even though we may not feel the need to drink during a chilly run, it is important even at those slower paces.

So is there a too cold? I think each individual needs to determine this for himself or herself based on experience, health, equipment and tolerance to the elements. My simple advice is if you have a tempo run or speed work on your schedule and it’s below zero, then you should complete the workout inside to air on the side of caution. On the other hand, if you are simply logging miles and don’t mind braving the elements then head outside.

In the cold, always layer up and keep skin covered in order to protect yourself from frostbite and if you are running on icy or slick conditions, put some sheet metal screws in your shoes or wear a pair of microspikes. Staying close to home doing smaller loops provides you with the option to swap out bottles if yours freeze and gives you a place to warm up quickly if needed. If you are running in the cold and something feels amiss, head inside and call it a day. Or finish your run on a treadmill. Stay safe, and I will keep dreaming of warmer temperatures and clear trails.

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